IOSR Journal Of Pharmacy (e)-ISSN: 2250-3013, (p)-ISSN: 2319-4219 www.iosrphr.org Volume 5, Issue 4 (April 2015), PP. 19-23 Acute Laryngitis and Croup: Diagnosis and Treatment Murtaza Mustafa1,P.Patawari2,RK.Muniandy3,MM.Sien4, MTH.Parash5,J.Sieman6 1-6Faculty of Medicine and Health Sciences,University Malaysia Sabah ,KotaKinabalu, Sabah,Malaysia. ABSTRACT: Croup is a common respiratory tract infection, among children between 6 months and 5-6 years. Croup is characterized by “barking cough”, resembling the call of a seal or sea lion. The stridor is worsened by agitation or crying, and it can be heard at rest, it may indicate critical narrowing of the airways.The virus initially infects the upper respiratory tract and usually produce congestion of the nasal passages and nasopharynx, subsequently, the larynx, the trachea and bronchi are involved. The classic croup- stridor, hoarseness, and cough-arise mostly from the inflammation of larynx and trachea.Parainfluenza virus type 1 is the most frequent cause of croup,with adenoviruses, enteroviruses and Mycoplasma pneumonia.Diagnosis is on clinical manifestations, and the history especially for the younger children.Roentgenographic evaluation is unnecessary, the radiologic picture may be helpful in differential diagnosis. Guidelines for management of croup have been classified as mild,moderate and severe, Westley score of 0 to 2 mild cases, moderately severe score 3 to 7,severe cases with a score of 8 to 11,and high risk score of12 to 17 with imminent respiratory failure.Dexamethosone and budesonide are effective, nebulized epinephrineracemic epinephrine or1- epinephrine may be added to the dexamethasone for severe croup. KEY WORDS:Croup, Barking cough,Viralcroup,Diagnosis and Treatment. I. INTRODUCTION Croup or laryngotracheobronchitis is a respiratory condition that is usually triggered by an acute viral infection of upper airway. The infection leads to swelling inside the throat, which interferes with normal breathing and produces the classical symptoms of a “barking” cough, stridor, and hoarseness [1].Croup affects about 15% of children, and usually presents between the ages of 6 months and 5-6 years[2].It accounts for about 5% of hospital admissions in this population[3].In rare cases, it may occur in children as young as 3 months and as old as 15 years[3].Males are affected 50% more frequently than females, and there is an increased prevalence in autumn[2].In a Seattle prepaid group practice, the annual incidence of croup was 7 per 1000 for all children younger than 6 years, and peak in incidence in the second year of life was 14.9%[4].In North Carolina, much higher rates were observed in all ages with a peak incidence in the second year of life of 47 annual episodes per 1000 children[5].Hospital admissions have significantly declined in recent years and in correlation with use of effective outpatient therapy for croup[6].In Ontario, the estimated annual rates of hospitalization from 1988- 2002 also showed a decline among children younger than 5 years, and rates were lower among children 1 to 4 years than among infants[7].Parainfluenza virus type 1 is the most frequent cause of croup. Parainfluenza viruses types 2 and 3 and influenza A also are major agents. Less common causes of croup are respiratory syncytial virus(RSV),influenza B virus, rhinoviruses, adenoviruses,enteroviruses,rubeola virus and Mycoplasma pneumonia [5]].Croup is diagnosed on clinical grounds once potentially more severe causes of symptoms have been excluded(i.e.epiglottis or an airway foreign body)[1].Children with croup are generally kept as calm as possible. Steroids are given routinely; with epinephrine used in severe cases [8].Children with oxygen saturations under 92% should receive oxygen [2].Dexamethasone and budesonide are effective in relieving the symptoms of croup as early 6 hours after treatment. [9].The paper reviews the current literature, diagnosis and management of croup in clinical practice. II. HISTORY AND NOMENCLATURE Home in 1765 first introduced the word croup in his treatise “An Inquiry into the Nature, Causes and Cure of the Croup” in which he described 12 patients with croup[10].The term croup descended from an Anglo Saxon word kropan or the old Scottish term roup, which means “to cry in a shrill voice”[11].For the next century, the term croup was applied to numerous probably viral and bacterial diseases, which included diphtheria,”cynache trachealis”which was often called”membranous” or”true” croup as opposed”spasmodic”or” flase”croup. Differentiation awaited Klebs’ discovery of Corynebacterium diphtheria in 1883.In 1948 Rabe[12],classified the forms of infectious croup according to etiology-bacterial or nonbacterial-and suggested that the latter larger group was viral in origin. He was able to identify the pathogen- C.diphtheriae or Haemophilusinfluenzae type b-in only 15% 0f 347 patients. 19 Acute Laryngitis and Croup… The term croup now generally refers to an acute respiratory illness characterized by a distinctive barking cough,hoarsness, and inspiratory stridor in a young child,usually between six months and three years old. This syndrome results from inflammation of varying levels of the respiratory tract, which sometimes spreads to the lower respiratory tract, producing concomitant lower tract findings.Croup is primarily laryngotracheitis and encompases a spectrum of infections from laryngitis to laryngotrecheobronchitis and sometimes laryngotracheobronchopneumonia[2].Most common among the clinical argot of croup are recurrent, allergic, and spasmodic croup. Most children develop croup only once or twice despite multiple infections with viruses that are prime etiologic agents. Some children have recurrent episodes of croup however, which is often referred to as “spasmodic croup”. Spasmodic croup and “allergic croup” also have been applied to cases that tend to be sudden in onset, often at night, with minimal coryza and fever, and that occur among children with a family history of croup or atopic. Spasmodic croup generally cannot be differentiated from a single episode of the usual type of croup, however, in its clinical manifestations or in its etiology, which is usually viral [2]. III. ETIOLOGIC AGENT Croup is usually deemed to be due to a viral infection[13].Among children evaluated for croup in emergency department one or more viral agents were identified in 80% of specimens by reverse transcriptase polymerase chain reaction(RT-PCR);the parainfluenza viruses were detected more frequently[14].No matter what means of detection were used, studies over decades have consistently shown that the parainfluenza viruses especially type 1 are the most frequent cause of croup[2].Only the parainfluenza viruses are associated with the major peaks of occurrence of croup cases Parainfluenza type 1 has been identified in approximately one fourth to one third of cases. Parainfluenza type 3 generally is the second most commonly associated virus, accounting for about 6% to 10% of cases depending on the year and circulating strain .Similarly, although respiratory syncytial virus(RSV) infections are particularly prevalent among this group, relatively few(about 5% of RSV infections) manifest as croup. More recent studies using RT-PCR methods have detected rhinoviruses,enteroviruses,and bocaviruses in 9% to 13% of specimens from children with croup. In many cases, another viral agent was concurrently identified. Confections with rhinoviruses are particularly frequently[14].Among children presenting with croup in an emergency department, two thirds of specimens with rhinovirus had another agent concurrently by RT- PCR.Adenoviruses and human metapneumovirus were identified in 1% to 2% of these children with croup Mycoplasma pneumonia was detected rarely among the croup cases(0% to 0.7%)[14].Limited information exists suggesting that coronaviruses cause a small proportion(about 2%) of croup cases.A study of more recently discovered human coronaviruses NL63 suggests, however, that this agent is highly associated with croup when detected in high titer and as a single agent[15].Outbreaks in the United States and elsewhere serve as a reminder that rubeola in the prevaccine era often resulted in severe and complicated croup. During the 1989-1999 upsurge of measles cases in the United States, laryngotracheobronchitis complicated approximately 20% of the cases of measles among hospitalized patients in Los Angeles and Houston[16].Children with croup as a complication of measles tended to be, the younger, they had a more severe course, and 17% to 22% required intubation. In some children, the outcome was fatal. IV. PATHOPHYSIOLOGY The viral infection that cause croup leads to swelling of the larynx,trachea, and large bronchi due to infiltration of white cells(especially histiocytic, lymphocytes, plasma cells, and neutrophils).Swelling produces airway obstruction which, when significant, leads to the dramatically increased work of breathing and the characteristic turbulent, noisy airflow known as stridor[8,3].The virus initially infects the upper respiratory tract and usually produces congestion of the nasal passages and nasopharynx.Subsequently especially during the primary infection, the larynx, the trachea, and sometimes bronchi become involved.The classic signs of croup- stridor, hoarseness, and cough-arise mostly from the inflammation of the larynx and trachea.The resulting is greatest at the subglottic level because this is the least distensible part of the airway as it is enriched by the cartilage,